Several types of cloud organization often appeared east of the island chain on Defense Meteorological Satellite Program (DMSP) visible images. The DMSP, using the F-8 and F-9 polar-orbiting satellites, provided 500x500 sq km fields of view, with a resolution of about 0.5 km during the daylight hours. The NCAR/ATD CP4 radar located at the Hilo Airport (just south of 20 deg N latitude and west of 155 deg W longitude) on the Big Island conducted low-level scans of clouds toward the east of the Island. Early morning cloud clusters within the incoming easterly trade wind are illustrated at 1701 UTC Display Image (182 K) (about one hour after sunrise, local time is UTC-10 hours) on 23 July 1990. These cloud clusters, when viewed with the CP4 radar, contained embedded convective cells and rainbands. By 1922 UTC Display Image (118 K) (about 3.5 hours after sunrise), several cloud clusters remain while an arc-shaped cloud line that extends south from Cape Kumukahi now delineates the flow separation line around the Island. The cloud textures and ocean surface in these images appear different due to the change in sun angle, which results in different shadowing by clouds and reflections from the ocean surface.
